1. Field of Invention
The present invention relates to an electrical connection box suitable for mounting on a vehicle, an industrial product such as a vehicle or robot, and more particularly an electrical connection box containing bus bars and relay terminals.
2. Description of Related Art
Electric and electronic parts for a vehicle are mounted in a vehicle body by accommodating them in or on an electrical connection box. JP-A-62-172219 shows an example of a known electrical connection box, which includes a circuit member comprising bus bars in layers, a plurality of relay terminals and a molded plastic material case. Upwardly projecting male tabs are formed by bending the bus bars and projecting them through the topmost insulating plate. The relay terminals are fitted on the male tabs. The case covers the relay terminals and has openings for terminals of a component which make contact with the relay terminals during use. In this type of arrangement there is a risk of water or other liquids penetrating into the case, leading to a possible leak current between the terminals.
Accordingly, it is an object of the present invention to provide an electrical connection box capable of preventing or minimizing the risk of current leaks caused by the penetration of water or other liquids into the case.
According to one embodiment of the invention there is provided an electrical connection box having a plurality of bus bars providing at least two upstanding tabs acting as terminals, with relay terminals fitted on the tabs. An insulation plate overlies the bus bars and has respective apertures through which the tabs project. The electrical connection box has at least one upstanding wall located between the apertures and having an inclined upper end face. The insulation plate covers a case member and is assembled on the insulation plate by a downward movement relative to the insulation plate. Walls providing respective housing spaces for the relay terminals are included in the case member. The walls include a partitioning wall separating an adjacent pair of said housing spaces.
The partitioning wall is arranged to make sliding contact with the upstanding wall during the downward movement and the partitioning wall and the upstanding wall in the assembled state at least partly surround a liquid-receiving space.
In the construction of the invention, the upstanding wall of the insulation plate stands up between the pair of tab apertures, which are close to each other. When the insulating plate and the case member are combined with each other, the upstanding wall slidably contacts the partitioning wall separating the corresponding relay terminals. In this way a direct open path does not exist between the relay terminals. Therefore the respective housing spaces accommodating the relay terminals are separate from each other. In this case, even if water or other liquid penetrates into the housing spaces, it is possible to minimize risk of a current leak being generated between the relay terminals. Any path between the relay terminals is an elongate one, including the liquid-receiving space, in which water collects and can be drained to the exterior.
Further, the inclined face at the upper end of the upstanding wall is capable of restricting or controlling the flow direction of water, or the like which flows from above, along the partitioning wall. This may also help to prevent a current leak from being generated between the relay terminals. Preferably in the assembled state, the inclined upper end face of the upstanding wall slopes upwardly away from the partitioning wall. Preferably, the insulation plate has two such upstanding walls arranged alongside each other between the apertures, and the partitioning plate is slidably received between the two upstanding walls, the liquid-receiving space being located between the two upstanding walls below the partitioning wall.
It is also preferable that the upstanding wall has a step providing a horizontal surface, at least one of the relay terminals being located on this horizontal surface. The step having the horizontal surface perpendicular to the extension direction of the male tab is formed preferably in the vicinity of the base of the upstanding wall, adjacent to the tab aperture. The relay terminals are fitted on the male tabs respectively, with one or more of the relay terminals located on the horizontal surface of the step. Therefore the relay terminals are stably located, when fitted on the male tabs. Accordingly, it is possible to reduce the possibility of deformation of the male tabs and the relay terminals, and inaccurate location of the relay terminals.
Preferably the walls of the case member further include at least one outer side wall bounding the housing spaces. The outer side wall having an inclined inner face portion which slopes upwardly and inwardly with respect to the housing spaces. In this way, water or the like which flows from above along the inner surface of the outer side wall can be discharged easily to the outside. That is, water collection in the terminal housing space is minimized.